1. Field of the Invention
The present invention relates to a recording apparatus for recording information on a recording medium by emitting an ink from a recording head and also to a method of controlling the operation of the recording apparatus.
More particularly, the present invention relates to a recording apparatus including a plurality of storage means for storing ink to be emitted by a recording head wherein each storage means can be replaced by a new one or can be refilled with ink independently of the other ones, and also to a method of controlling the operation of such a recording apparatus.
2. Description of the Related Art
In a serial type recording apparatus, a recording head serving as recording means mounted on a carriage moves across a recording medium (hereinafter also referred to as a recording sheet) in the main scanning direction substantially perpendicular to the direction (secondary scanning direction) in which the recording medium is moved thereby recording an image on the recording medium in the main direction. After completion of the recording along one line in the main scanning direction, the recording medium is moved by a fixed amount in the paper feeding direction. After that, an image is recorded on the recording medium at rest along the next line in the main scanning direction. The above operation is performed repeatedly until the image is formed over the entire recording area of the recording medium.
Among various types of recording apparatus, a recording apparatus of the ink-jet type, in which recording is accomplished by emitting ink from a recording head serving as recording means toward a recording medium, has the following advantages:
1. The recording means can be easily realized into a small form.
2. A high-resolution image can be recorded at a high speed.
3. Recording on plain paper can be accomplished without needing a special process.
4. Running cost is low.
5. A low noise operation can be achieved because of the non-impact mechanism.
6. A color image can be easily recorded using inks with various colors.
In a line ink-jet recording apparatus with a line recording head having a large number of ink emission orifices formed along a line (extending in the main scanning direction) perpendicular to the paper feeding direction (secondary scanning direction), recording can be performed at a further increased speed.
Furthermore, if the ink is emitted in a substantially vertical direction, then the traveling path of the emitted ink is not bent by gravitation and thus the ink strikes exactly intended point on the recording medium. As a result, the resolution is further improved.
In the ink-jet recording apparatus, ink-jet recording means (recording head) of the type in which ink is emitted by means of thermal energy generated by driving an ink emission energy generating element includes an electro-thermal conversion element, electrode, liquid flowing path wall, and a top plate which are formed using a semiconductor fabrication process such as etching, evaporation, or sputtering. According to this technique, it is possible to easily produce an ink-jet recording head having a high-density of ink emission orifices, and thus it is possible to achieve a further reduction in the size of the recording head. By taking advantage of the integrated circuit fabrication technology or microfabrication technology, it is possible to produce recording means into a long form or into a plane (two-dimensional) form. This allows recording means to be mounted in a high-density fashion.
The recoding head used in the ink-jet recording apparatus generally has an array of ink emission orifices with a small size. However, if foreign particles such as paper dust or dirt deposits on the ink emission part of the recording head, or if the ink present in the emission path increases in viscosity, then the ink emission orifices are clogged. This causes a problem in the recording operation. When a new ink cartridge for supplying ink to a recording head or a new recording head cartridge including an ink cartridge and a recording head is used for the first time, the ink flowing path from the ink cartridge to the ink emission orifices of the recording head is not expected to be in a normal state. To recover the ink flowing path into a normal state, there is provided cleaning means for removing foreign particles from the ink emission part (where ink emission orifices are formed) of the recording head, and/or there is provided recovery means for recovering the state of the ink emission orifices and the ink flowing path of the recording head.
One known cleaning means is a flexible wiper (wiping member) by which the ink emission plate of the recording head is wiped thereby cleaning it. One known recovery means is a combination of a cap and a pump wherein the cap is capable of covering the ink emission plate of the recording head and is connected to the pump such that the emission orifices can be sucked by the pump. In the recovery means having such a structure, the ink emission energy generation elements disposed in the ink emission orifices are driven so that ink is emitted from the ink emission orifices toward the cap (hereinafter such an emission process is also referred to as preliminary emission), or the ink emission orifices are sucked by the pump so as to force the ink to be discharged from the emission orifices while covering the ink emission plate with the cap, thereby eliminating the factors which can cause a failure in the recording operation. When no recording operation is performed, the recording head is placed at its home position and the ink emission orifices of the recording head are covered with the cap so that the ink emission orifices are prevented from encountering problems.
In the art of the ink-jet recording apparatus, it is also known to provide remaining ink detection means for detecting the amount of ink remaining in an ink cartridge and also provide means for informing a user of the amount of remaining ink and/or the timing of replacing the ink cartridge, depending on the detection result given by the remaining ink detection means.
The recording head cartridge and the cap serving as the recovery means used in the conventional ink-jet recording apparatus are further described below with reference to FIG. 15. In the specific example shown in FIG. 15, the recording head and the cap are formed in a small size and capable of recording a color image.
In FIG. 15, the recording head cartridge and the cap are denoted by reference numerals 11 and 20, respectively. The recording head cartridge 11 can emit a plurality of inks with colors of black (Bk), cyan (C), magenta (M), and yellow (Y). Ink emission orifices (11c=Bk, 11d=C, 11e=M, 11f=Y) for emitting the plurality of inks are formed in a single ink emission plane 6h. The inks are supplied from a black (Bk) ink cartridge 12 or a color ink cartridge (three colors Y, M, C are stored in the single cartridge) 13 (refer to FIG. 2). The single cap 20 is used in common for all the ink emission orifices. When a recovering operation is performed, the cap 20 comes into contact with the ink emission plane 6h of the recording head cartridge 11 and the respective ink emission orifices formed in the ink emission plane 6h are simultaneously sucked by a pump (not shown in FIG. 15) connected to the cap 20.
Referring to the flow charts shown in FIGS. 16-18, the procedure of replacing an ink cartridge used in the conventional ink-jet recording apparatus is described below.
The procedure of replacing the ink cartridges of the conventional ink-jet recording apparatus is described below with reference to the flow charts shown in FIGS. 16 to 18.
After turning on the electric power of a new recording apparatus (step S201), a recording head cartridge 11 is set on a carriage 6 (refer to FIG. 2). Furthermore, a new black (Bk) ink cartridge 12 and color ink cartridge (in which all three color inks are stored) 13 are set on the recording head cartridge 11 (step S202). The count numbers of the remaining-ink counters V(Bk), V(Y), V(M), and V(C) of Bk, Y, M, and C (not shown) provided in the ink-jet recording apparatus are each set to maximum values (step S203).
After that, a recovering operation is performed to get the recording head recovered into a normal state. The amount of ink consumed by suction and preliminary emission in the recovering operation is calculated for each ink on the basis of the evacuating capacity of the pump 25 (refer to FIG. 2), the amount of ink per droplet, and the number of droplets emitted. The amounts of inks consumed in the recovering operation are set into the variables V(Bk).sub.1, V(Y).sub.1, V(M).sub.1, and V(C).sub.1, respectively (step S204).
The count values of the remaining-ink counters V(Bk), V(Y), V(M), and V(C) are updated by subtracting the consumed amounts from the current count values of the remaining-ink counters (step S205). The count values of the remaining-ink counters V(Bk), V(Y), V(M), and V(C) of the respective inks are checked whether they are equal to or less than zero (step S206). If the count value of any of the remaining-ink counters of ink Bk, Y, M, or C is detected to be equal to or less than zero, then the process goes to step S114.
If the count value of the remaining-ink counter V(Bk) of the Bk ink is equal to or less than zero, a message is displayed to tell that the black (Bk) ink cartridge 12 should be replaced. On the other hand, if the count value of any remaining-ink counter V(Y), V(M), or V(C) of Y, M, or C ink is equal to or less than zero, then a message is displayed to tell that the color ink cartridge 13 should be replaced. In the case where the count value of the remaining-ink counter V(Bk) of Bk ink is equal to or less than zero and the count value of any-remaining ink counter V(Y), V(M), or V(C) of Y, M, or C ink is also equal to or less than zero, a message is displayed to tell that both the black (Bk) ink cartridge 12 and the color ink cartridge should be replaced (step S207). The process then goes to step S216.
On the other hand, if it is determined in step S206 that the count values of the remaining-ink counters V(Bk), V(Y), V(M), and V(C) of Bk, Y, M, and C are all greater than zero, then the process waits in step S208 until a recording command is issued. If a recording command is received (step S209), then recording is performed on one page of recording sheet (step S210) and the amount of ink consumed in the recording operation is calculated for each ink. Herein the calculation can be accomplished on the basis of the amount of one droplet of ink and the number of droplets of each ink used in the recording operation. The amounts of inks consumed in the recording operation are substituted into the variables V(Bk).sub.2, V(Y).sub.2, V(M).sub.2, and V(C).sub.2, respectively (step S211).
After completion of the recording operation on one page of recoding sheet, the count values of the remaining-ink counters V(Bk), V(Y), V(M), and V(C) are updated by subtracting the consumed amounts from the current count values of the respective remaining-ink counters (step S212). The count values of the remaining-ink counters V(Bk), V(Y), V(M), and V(C) of the respective inks are checked whether they are equal to or less than zero (step S213). If the count value of any remaining-ink counter V(Y), V(M), or V(C) of Y, M, or C ink is equal to or less than zero, then the process goes to step S114.
If the count value of the remaining-ink counter V(Bk) of the Bk ink is equal to or less than zero, a message is displayed to tell that the black (Bk) ink cartridge 12 should be replaced. On the other hand, if the count value of any remaining-ink counter V(Y), V(M), or V(C) of Y, M, or C ink is equal to or less than zero, then a message is displayed to tell that the color ink cartridge 13 should be replaced. In the case where the count value of the remaining-ink counter V(Bk) of Bk ink is equal to or less than zero and the count value of any remaining-ink counter V(Y), V(M), or V(C) of Y, M, or C ink is also equal to or less than zero, a message is displayed to tell that both the black (Bk) ink cartridge 12 and the color ink cartridge 13 should be replaced (step S214). The process then goes to step S216.
On the other hand, if it is determined in step S213 that the count values of the remaining-ink counters V(Bk), V(Y), V(M), and V(C) of Bk, Y, M, and C are all greater than zero, then the process goes into a waiting state and waits for a recording command (step S215).
After completion of step S207 or S214, the process goes to step S216 in which the ink cartridge whose remaining amount counted by the remaining-ink counter has become zero is replaced. The count value of the remaining-ink counter associated with the replaced ink cartridge is reset to the maximum value (step S217). A recovering operation is then performed to get the ink flowing path associated with the replaced ink cartridge recovered into a normal state, and the amount of ink consumed in the recovering operation is calculated (step S218). The count values of the remaining-ink counters V(Bk), V(Y), V(M), and V(C) are updated by subtracting the consumed amounts from the current count values of the remaining-ink counters (step S219).
The count values of the remaining-ink counters V(Bk), V(Y), V(M), and V(C) of the respective inks are checked whether they are equal to or less than zero (step S220). If the count value of any of remaining-ink counters of Bk, Y, M, or C ink is detected to be equal to or less than zero, then the process goes to step S114.
If the count value of the remaining-ink counter V(Bk) of the Bk ink is equal to or less than zero, a message is displayed to tell that the black (Bk) ink cartridge 12 should be replaced. On the other hand, if the count value of any remaining-ink counter V(Y), V(M), or V(C) of Y, M, or C ink is equal to or less than zero, then a message is displayed to tell that the color ink cartridge 13 should be replaced. In the case where the count value of the remaining-ink counter V(Bk) of Bk ink is equal to or less than zero and the count value of any remaining-ink counter V(Y), V(M), or V(C) of Y, M, or C ink is also equal to or less than zero, a message is displayed to tell that both the black (Bk) ink cartridge 12 and the color ink cartridge 13 should be replaced (step S221). The process then goes to step S216.
On the other hand, if it is determined in step S220 that the count values of the remaining-ink counters V(Bk), V(Y), V(M), and V(C) of Bk, Y, M, and C are all greater than zero, then the process goes into a waiting state and waits for a recording command (step S222).
In either step S206, 213, or 220, described above, if it is determined that the count value of at least one of the remaining-ink counters V(Y), V(M), V(C) associated with inks Y, M or C in the color ink cartridge or the count value of the remaining-ink counter V(Bk) of the Bk ink is equal to or less than zero and that although the count value of some remaining-ink counter is greater than zero, it is less than the amount of ink (Bk: V(Bk).sub.1, Y: V(Y).sub.1, M: V(M).sub.1, C: V(C).sub.1) used in the recovering operation, the ink cartridge that was determined by the remaining-ink counter to have no remaining ink is replaced in step S216, and the count value of the remaining-ink counter associated with the replaced ink cartridge is reset to the maximum value in step S217. Then in step S218, the recovering operation is performed and the amounts of ink used in the recovering operation are calculated. In the following step S219, the values of the respective remaining-ink counters are updated according to the calculation result. In this case, when the process goes to step S220, the count value of the remaining-ink counter of the ink cartridge which was not replaced becomes equal to or less than zero. Thus the process goes to step S221 and a message telling that the ink cartridge should be replaced is displayed. Subsequently, steps S216 to S220 are again performed. After that, the process waits in step S222 until a recording command is issued. Depending on the amounts of remaining inks, as described above, there is a possibility that another ink cartridge is required to be replaced immediately after replacing some ink cartridge, before starting a recording operation.
The procedure described above with reference to FIGS. 16-18 has the following problems.
1. After replacing some ink cartridge, it is desirable to perform a recovering operation to get the ink flowing path associated with the replaced ink cartridge recovered into a normal state. However, the recovering operation causes a reduction in the remaining amount of inks of the ink cartridges which were not replaced. As a result, it is often required to replace another ink cartridge immediately after the replacement of one ink cartridge. When another ink cartridge is replaced immediately after replacing one ink cartridge, the ink cartridge which was first replaced is subjected to two successive recovering operations before restarting the recording operation and thus the ink is wasted.
2. When another ink cartridge is replaced immediately after replacing one ink cartridge, the recovering operation is successively performed twice and thus the total time needed for the recovering operation becomes longer.
Japanese Patent Laid-Open No. 9-156126 discloses a technique in which the amount of remaining ink is monitored for each of a plurality of color inks and the remaining amount is indicated for each color wherein if the remaining amount of some ink becomes smaller than a predetermined value, the user is informed that the ink cartridge should be replaced. The patent also discloses a technique of informing the user that the amount of remaining ink has decreased to a considerably low level at a proper time before it becomes necessary to replace the ink cartridge. However, in this technique disclosed in the patent cited above, information is presented to the user only about the ink cartridge of a plurality of ink cartridges which has become smaller in the remaining amount than the predetermined value, and the possibility of a problem is not taken into account that can occur due to a reduction in the amount of remaining ink during the recovering operation performed after the replacement of an ink cartridge.
In Japanese Patent Laid-Open No. 5-16384, there is disclosed a technique in which the amount of remaining ink is monitored for each of a plurality of inks, and if an ink with a certain color is detected to be smaller in the remaining amount than a predetermined value, information is presented to the user that the ink cartridge should be replaced after further performing a certain amount of recording operation. The patent cited above also discloses a technique in which if the remaining amount of another color ink is detected to become less than the predetermined value during the recording operation performed after the detection of a reduction in the remaining amount of a certain color ink, a message is also displayed to tell that the ink cartridge of that color should also be replaced. However, the problem described earlier is not taken into account even in this patent.
In U.S. Pat. No. 5,414,452, a technique is disclosed in which the amount of remaining ink is detected on the basis of the number of ink droplets emitted and the reduction in the amount of ink due to evaporation. However, the problem described above is not take into account also in this patent.